I live off of a well, water softner, choroline system. Water is good, no rust marks, can wash clothes and drink it.

I noticed my tank behind the toilet is "slimey". Not sure what is causing this, lack of use, we do go for extended camping trips this time of year. Not sure if I can add anything to clear this out. Choroline tablet, but would that hurt my sand mound as well.

Pour a cup of liquid bleach in the holding tank & scrub with toilet brush the best you can--I hate to be the bearer of bad news, but a lil elbow grease is still the best tool in the world---then flush, it won't hurt a thing plus give you some exercise-- --cs, you forgot the elbow grease part

If its black slime you might kill some of it not most of it. Black slime is caused by iron eating bacteria and the only way to get rid of it is to get rid of the iron in the water with a green sand filter . If you have a chlorinating system already youve confirmed that chlorine does not do it. Wont hurt anything but .... Im not a chemist ,but I did stay at a Holiday Inn express the other day

I had the same slime. Plus an odor that would get better or worse depending on time of year (water temperature and water table level) Best I could tell it was from the Iron bacteria. I had nothing previous, just well, pump, and house. I put a filter in the system and my water is now wonderful. I change it every 3-6 months, again depending on the time of year. It's just an element type filter.

Chlorine every once and in while and a little scrub won't hurt, just don't use one of those chlorinating tablets. Chlorine drys out all the seals and washers in your toilet tank, and can cause leaks. You will get rid of the slime and smell and come home to a leak on the floor.